US study points to genetic changes making teenagers more prone to alcoholism and anxiety in later life

Teenagers who binge drink could be damaging the development of their brains, making them more prone to psychiatric disorders including alcoholism in later life, new US research suggests.

Lab tests found that rats exposed to intermittent doses of doses of alcohol during the adolescent phase of their development were more likely to display symptoms like anxiety in later life.

They were also more attracted to drink as adults than other rats, the tests at University of Illinois at Chicago (UIC) found.

The study, published in the journal Neurobiology of Disease, found evidence that binge drinking effectively changed the shape of the DNA in the animals’ brains at a crucial stage of their development.

Tissue analysis showed that the DNA was wrapped more tightly around proteins in those rats which had been exposed to binge drinking conditions as adolescents than in those which had not, as a result of chemical changes.

The team, led by Prof Subhash Pandey, director of neuroscience alcoholism research at UIC’s Chicago College of Medicine, believe they have found the mechanism by which binge drinking affects people in later life.

“This may be the mechanism through which adolescent binge-drinking increases the risk for psychiatric disorders, including alcoholism, in adulthood,” said Prof Pandey

But they also found that the effects could also potentially be treatable. When some of the rats were given a cancer drug, the DNA was observed to be less tightly coiled.

“We aren’t sure if the drug needs to be given long term during adulthood in order to completely reverse the harmful effects of adolescent alcohol exposure,” Prof Pandey added.

To simulate conditions like those of heavy drinking sessions in teenagers researchers took a group of four-week-old rats and gave them alcohol for two days, followed by two days off, repeating the pattern for almost a fortnight.

“Our study provides a mechanism for how binge-drinking during adolescence may lead to lasting [epigenetic] changes … that result in increased anxiety and alcoholism in adults,” said Prof Pandey.

“Intermittent alcohol exposure degrades the ability of the brain to form the connections it needs to during adolescence.

“The brain doesn’t develop as it should, and there are lasting behavioural changes associated with this.”

It found that 28 per cent of Britons were classed as having had episode of heavy drinking in the previous month – almost twice as much as the global average – putting the UK 13th highest for heavy drinking out of 196 countries – worse than Estonia, Ukraine, Belarus and Hungary.

Binge drinking – measured as the number of people who had a heavy drinking session in the week before the ONS General household Survey – fell by almost 17 per cent across the wider population between 2005 and 2013, but almost twice as fast among young people.

Strikingly, the number of under-25s who do not drink alcohol at all has leapt by 40 per cent in just eight years.

More than a quarter of young people abstain altogether. A third of people living in London – the youngest region of the UK in demographic terms – are now teetotal.